Oxidation of cobalt and manganese in seawater via a common microbially catalyzed pathway

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

9

Scientific paper

Cobalt and manganese uptake onto suspended particles was studied in waters collected from Waquoit Bay, Massachusetts and the upper water column of the Sargasso Sea using radiotracers, coupled with protocols used previously for Mn and Ce to distinguish biological and redox processes. Cobalt uptake onto suspended particles in Waquiot Bay was dominated by microbial oxidation. Moreover, there was a close relationship between Mn(II) and Co(II) oxidation, with Mn(II) specific rates approximately 7-10x faster. Oxidation of each element obeys Michaelis Menten kinetics, with identifical values of K m in a given sample and values of V max are 7× higher for Mn. Lineweaver-Burk plots, generated from saturation plots for Co and Mn oxidation at different Mn and Co concentrations, demonstrated competitive inhibition between Co and Mn. The results indicate that both elements are co-oxidized via the same microbial catalytic pathway, and that this is probably an important mechanism for the incorporation of Co into marine Mn oxides. In the Sargasso Sea, by contrast, Mn and Co uptake onto suspended particles were completely decoupled. Cobalt uptake was nonoxidative, biologically mediated, and enhanced by low to moderate levels of light. It is probably due primarily to uptake by phytoplankton. Manganese uptake was almost exclusively oxidative and was inhibited by light even at low intensities. The differences probably reflect a higher biological demand for Co in the Sargasso Sea (Co is a biologically essential element), where Co concentrations are low, and lower activity of Mn oxidizing bacteria. Results suggest that higher specific uptake rates of Co than Mn by phytoplankton in oceanic regimes could result in Co having a geochemistry intermediate between Mn and a more nutrient-type element, such as Zn. Nevertheless, Co and Mn cycling are expected to be closely coupled in regions of high microbial Mn oxidizing activity.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Oxidation of cobalt and manganese in seawater via a common microbially catalyzed pathway does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Oxidation of cobalt and manganese in seawater via a common microbially catalyzed pathway, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Oxidation of cobalt and manganese in seawater via a common microbially catalyzed pathway will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1462684

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.